Energy & Enzymes, Cell Resipration, Photosynthesis

Front 1

Disorder happens

Back 1

spontaneously

Front 2

Organization requires

Back 2

Energy

Front 3

entropy gain

Back 3

All energy transformations result in an
increase of “disorder”

Front 4

free energy (G

Back 4

Useful energy = Gibbs

Front 5

Metabolism

Back 5

the sum of all
biochemical
reactions in a cell

Front 6

Two kind of
metabolism

Back 6

Anabolism
synthesis reactions
(building something)

Catabolism
decomposition reactions
(breaking something down)

Front 7

The capacity to do “work”

Back 7

Energy

Front 8

Different types of energy

Back 8

potential energy
•
kinetic energy
•
chemical energy (energy in bonds)
•
radiation energy (light)
•
nuclear energy
•
heat (kinetic energy of molecules)

Front 9

Heat energy is measured in

Back 9

Kilocalories

Front 10

One calorie = the amount of heat required to raise the
temp of 1 g water by 1C

Back 10

1 food Calorie = 1 kilocalorie (kcal) = 1000calories

Front 11

First law of thermodynamics

Back 11

Any form of energy can be transformed to other
forms of energy, but energy is never lost or
created.
The sum of all energy is always the same
•energy cannot be lost-only converted

Front 12

Second Law of Thermodynamics:

Back 12

disorder is more likely than order
•Entropy is always increasing
Entropy = disorder in the universe

Front 13

Free energy change ^ (G)

Back 13

The amount of energy needed for a reaction to proceed

Front 14

exergonic reaction:

Back 14

releases energy

Front 15

endergonic reaction

Back 15

Gains energy

Front 16

Activation energy

Back 16

energy needed to get a reaction started

Front 17

Catalysts

Back 17

substances that lower the activation energy of a reaction

Front 18

ATP

adenosine tri-phosphate

Back 18

energy from exergonic reactions is used to fuel endergonic reactions

Front 19

Enzymes

Back 19

molecules that catalyze reactions in living cells

Front 20

Enzymes are very

Back 20

specific

Front 21

substrate

Back 21

The reactant(s) that are used to accelerate a reaction

Front 22

Inhibitors

Back 22

are molecules that bind to the enzymes and decrease activity

Front 23

competitive inhibitors

Back 23

compete with the substrate for binding to the same active site

Front 24

Activators

Back 24

molecules that bind to the enzymes and increase activity

Front 25

Cofactors

Back 25

non- protein molecule/atom required for enzyme activity

Metal or co-enzyme (like
vitamins

Front 26

Feedback
inhibition

Back 26

when the initial enzyme is inhibited by the final product

Front 27

All organisms use cellular respiration to

Back 27

extract energy from organic molecules
•
Glucose to ATP
It occurs in all tissues at all times

Front 28

autotrophs

Back 28

are able to produce their own organic
molecules through photosynthesis

Front 29

heterotrophs

Back 29

live on organic compounds produced by other organisms

Front 30

A redox reaction

Back 30

where one reactant is
oxidized (loses e-) and the other reactant is
reduced (gains e-)

Front 31

Nicotinamide adenine dinucleotide (NAD+,becomes NADH)

Back 31

used to move electrons in cellular respiration

NAD+ is an electron carrier •NAD+ accepts 2 electrons and 1 proton to become NADH

Front 32

Aerobic respiration

Back 32

In the presence of oxygen this large amount of energy must be released in small steps rather than all at once

Front 33

C6H12O6+ 6O2>6CO2+ 6H2O + 36 ATP + heat

Back 33

The equation for cellular respiration

Front 34

Steps of Cellular Respiration are:

Back 34

1 Glyucolysis
2 Pyruvate Oxidation (AcetylCoA)
3 The Krebs Cycle (Citric acid cycle)
4 Electron Transport Chain (ETC)
5 Chemiosmosis (Oxidativephosphorylation)

Front 35

Enzymatic reaction rate
is influenced by several
factors:

Back 35

Enzyme concentration
•
Substrate concentration
*all enzymes are busy
•
Environment
•
Regulatory molecules

Front 36

e- and H+ are transferred from glucose to
oxygen through a series of oxidations
•
High energy e- in sugars to low energy e- in CO2 and H2O

Back 36

Cellular Respiration

Front 37

Occurs outside the mitochondria
•
Splits the C6 sugar glucose into 2 C3 sugars called
pyruvate

Back 37

Glycolysis

Front 38

converted into Acetyl CoA
•
This gives off a CO2 and gives a NADH

Back 38

Pryruvate Oxidation

Front 39

The acetyl CoA enters the cycle and results in:
2 CO2 given off 3 NADH produced
1 ATP produced
1 FADH produced
•
*multiply times 2 to figure
out “per glucose”

Back 39

The Krebs Cycle

Front 40

The NADH and FADH give their electrons
electrons “tumble” down it losing energy as
they go
•
This results in protons being pumped out of the
inner mitochondrial membrane and creates a
proton gradient
•
The electron is given to O2 at the end
thus“aerobic respiration”

Back 40

Electron Transport Chain

Front 41

The protons accumulate and are passed back over
the membrane through the ATP
synthase
protein
•
For each proton that
comes through,
ADP + P is changed
into ATP

Back 41

Chemiosmosis
(Oxidative phosphorylation)

Front 42

Theoretical energy yields

Back 42

38 ATP per glucose for bacteria
•
36 ATP per glucose for eukaryotes

Front 43

Actual energy yield

Back 43

30 ATP per glucose for eukaryotes
•
reduced yield is due to “leaky” inner membrane
and use of the proton gradient for purposes other
than ATP synthesis

Front 44

use of inorganic molecules (other than O2) as final
electron acceptor

Back 44

anaerobic respiration

Front 45

use of organic molecules as final electron acceptor
Ethanol, lactic acid

Back 45

fermentation

Front 46

“switching over” to fermentation when O2 is not available

Back 46

facultative anaerobic

Front 47

the lack of O2 eliminates all steps but

Back 47

glycolysis

Front 48

important because many of the intermediates are starting molecules for other cell parts and functions

Back 48

Respiration

Front 49

Protons accumulate and are passed back to the other side ADP + P is turned back into ATP

Back 49

ATP synthase

Front 50

A polar molecule due to its oxygen that has a slight negative charge while its hydrogens have slight positive charge is a universal solvent and essential to all life

Back 50

water

Front 51

Power House of the cell, where ATP is made

Back 51

mitochondria

Front 52

Changed into ATP

Back 52

ADP + P

Front 53

Net total of energy made through cellular respiration

Back 53

36 ATP

Front 54

Eases the fall of electrons negative charge helps drive protons across membranes

Back 54

Proton Gradient

Front 55

Products of Glycolysis step #1

Back 55

2 ATP and 2 NADH+
pryruvic acid

Front 56

Products of Pryruvate Oxidation Step #2

Back 56

Acetyl CoA

Front 57

Products of the Krebs Cycle

Back 57

CO2
3 NADH 1 ATP and 1 FADH ( total is x 2)
and citric acid

Front 58

Has no products excpet it makes the proton gradient: oxygen is final electron acceptor
For each NADH 3 protons are pumped out
For each FADH 2 protons are pumped out

Back 58

Electron Transport Chain

Front 59

What organisms do both cellular respiration and photosynthesis

Back 59

Plants

Front 60

captures light energy from the sun and convert it to chemical energy stored in sugars and other organic molecules countered by cellular respiration

Back 60

photosynthesis

Front 61

Photosynthesis is carried out by:

Back 61

Cyanobacteria
•
7 groups of algae
•
all land plants

Front 62

The equation for cellular respiration

Back 62

6CO2 + 6H2O -> C6H12O6 + 6O2

Front 63

Photosynthesis takes place in

Back 63

chloroplasts

Front 64

internal membrane arranged in flattened sacs

contain chlorophyll and other pigments

Back 64

Thylakoid membrane

Front 65

Semi -liquid substance surrounding thylakoid membranes

Back 65

Stroma

Front 66

Capture energy from sunlight

Make ATP and reduce NADP+ to NADPH In thylakoid

Back 66

Light dependent reactions

Front 67

Use ATP and NADPH (from light reactions) to synthesize organic molecules from CO2 In stroma

Back 67

Carbon fixation reactions

Front 68

Photosynthesis is divided into:

Back 68

Light dependent reactions
and Carbon fixation reactions

Front 69

the main pigment in photosynthesis

Back 69

Chlorophyl

Front 70

Chlorophyll mainly absorbs light in the

Back 70

blue and red parts of the spectrum
No absorption in green and yellow

Front 71

increase the range of light wavelengths that
can be used in photosynthesis can protect the plant
from excess light
known as carotenoids

Back 71

accessory pigments

Front 72

a team of light-gathering molecules

Back 72

photosystem

Front 73

absorbs photons and excites
electrons that are passed on to a protein carrier

Back 73

Photosystem II- happens first

Front 74

absorbs photons and re-excites
electrons that are passed through carriers and
ultimately reduce NADP+ to NADPH

Back 74

Photosystem 1

Front 75

To build carbohydrates, cells need:

Back 75

Energy, reduction potential, a source of Carbon
This all happens in the Calvin Cycle

Front 76

Calvin cycle has 3 phases:

Back 76

1 carbon fixation
2 Reduction
3 regeneration of Rubisco (RuBp)

Front 77

This is the most abundant enzyme in the world

Back 77

ribulose bisphosphate carboxylase oxygenase
(rubisco)

Front 78

In most plants the enzyme that “fixes” CO2 from the air

Back 78

rubisco

Front 79

2 G3P are used to produce 1 glucose in reactions
in the cytoplasm
o
each G3P contains 3 carbons
•
18 ATP molecules
•
12 NADPH molecules

Back 79

Make one molecule of glucose

Front 80

There are two alternative methods of
photosynthesis that have evolved in high
temperatures and arid climates

Back 80

C4 metabolism
•
Crassulacean acid metabolism
(CAM)

Front 81

a loss of energy
•
inefficient photosynthesis
It is a problem when:
•
the temp is high
•
it is too dry

Back 81

Photorespiration

Front 82

Plants that only have rubisco have this
can combine with either O2 or CO2
occurs when rubisco binds with oxygen, instead of CO2

Back 82

Photorespiration

Front 83

Alternative methods use a different enzyme to
initially fix the CO2 from the air

Back 83

PEP carboxylase (PEPC)

Front 84

separate the process in space with the CO2 being fixed in the mesophyll cells, and the Calvin cycle in the bundle sheath cells

Back 84

C4 plants

Front 85

separate the process between
night and day by using malic acid to store the CO2

Back 85

CAM plants

Front 86

Are carried out in the thylakoid • Convert light energy into ATP and NADPH • Split water and release O2 into the air

Back 86

Light Reactions

Front 87

Is carried out in the stroma • Uses ATP and NADPH to convert CO2 into a C3 sugar (G3P) •CO2 is fixed from the air by rubisco or pepc

Back 87

Calvin Cycle

Front 88

chloorphyll b, xanthophylls, and carotenes

Back 88

accessory pigments

Front 89

Carbon dioxide reacting with water forms this and Dissociates in to bicarbonate ions and hydrogen ions

Back 89

carbonic acid

Front 90

Color least effective in plant growth

Back 90

Red because it absorbs the least amount of light